package hedron;

import java.util.HashMap;
import java.util.Iterator;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.plugin.AbstractUIPlugin;
import org.osgi.framework.BundleContext;

/**
 * The activator class controls the plug-in life cycle
 */
public class Activator extends AbstractUIPlugin {

	// The plug-in ID
	public static final String PLUGIN_ID = "HEDRON";

	// The shared instance
	private static Activator plugin;
	
	static HashMap<String, Image> imageCache = new HashMap<String, Image>();
	static HashMap<String, ImageDescriptor> descriptorCache = new HashMap<String, ImageDescriptor>();
	/**
	 * The constructor
	 */
	public Activator() {}

	/*
	 * (non-Javadoc)
	 * @see org.eclipse.ui.plugin.AbstractUIPlugin#start(org.osgi.framework.BundleContext)
	 */
	public void start(BundleContext context) throws Exception {
		super.start(context);
		plugin = this;
	}

	/*
	 * (non-Javadoc)
	 * @see org.eclipse.ui.plugin.AbstractUIPlugin#stop(org.osgi.framework.BundleContext)
	 */
	public void stop(BundleContext context) throws Exception {
		plugin = null;
		super.stop(context);

		for (Iterator<Image> i = imageCache.values().iterator(); i.hasNext();) {
			i.next().dispose();
		}
		imageCache.clear();
	}

	/**
	 * Returns the shared instance
	 *
	 * @return the shared instance
	 */
	public static Activator getDefault() {
		return plugin;
	}


	/**
	 * Returns an image descriptor for the image file at the given
	 * plug-in relative path
	 *
	 * @param path the path
	 * @return the image descriptor
	 */
	public static ImageDescriptor getImageDescriptor(String path) {
		ImageDescriptor descriptor = descriptorCache.get(path);
		if (descriptor == null) {
			descriptor = imageDescriptorFromPlugin(PLUGIN_ID, path);
			descriptorCache.put(path, descriptor);
		}
		return descriptor;
	}

	public static Image getImage(String path) {
		Image image = imageCache.get(path);
		if (image == null) {
			ImageDescriptor descriptor = Activator.getImageDescriptor(path);
			if (descriptor != null) {
				image = descriptor.createImage();
				imageCache.put(path, image);
			} else {
				Application.log.warning("Cannot load : " + path);
			}
		}
		return image;
	}
}
